In integrated circuits, several different design styles of lines are available for carrying electrical signals. For example, a static style of line may be driven by an inverter (such as a complementary metal-oxide-semiconductor or CMOS inverter) or by a non-inverting buffer. If the line is relatively long, it may be divided into several segments, and an inverter or non-inverting buffer may drive each segment in response to the signal received from the previous segment. In a precharge style of line, each line may be precharged to a certain logic level (for example, to a logic high), and then may be driven to a logic level representative of data (e.g., input/write data, output/read data, address data, command data, etc.) to be placed on the line. As used herein, a logic high may be a voltage associated with a voltage source node, such as VCC and may be, for example 1.35 v, whereas a logic low may be a voltage associated with a reference voltage node, such as ground. Typically, if there is a plurality of lines (for example, data read lines in a memory), all of the lines are precharged to the same logic level. Following precharge, the lines may be driven to a logic level representative of data to be placed on the line by selectively maintaining the precharged logic level, or by changing the logic level. Precharge style lines may be faster than static style lines, may have lower input capacitance, may have less contention (including during switching), may favor one logic level, and so forth.
Precharge style lines, however, may waste charge (and thus waste power) as a result of the precharging. For example, if a line or segment of line is precharged to a logic high, the charge required (“Q”) to precharge the line to a logic high will be wasted if the data to be placed on the line is a logic low because that charge will be discharged by, for example, coupling the line to a reference voltage node such as ground. In general, the longer the line, the greater the total capacitance the line will have, and, therefore, the more charge that may be wasted because the line will require a larger Q to precharge the line, which may be subsequently discharged. Also, in general, the faster the speed at which the line is operated, the more charge that may be wasted because the line will be precharged more frequently.
Integrated circuits in today's apparatuses generally include long lines and are operated at relatively fast operating speeds. At the same time, however, it is generally desirable to reduce power consumption in order to, for example, reduce heat and/or extend battery life for mobile apparatuses. As used herein, an apparatus may refer to a number of different things, such as circuitry, a memory device, a memory system (e.g., SSD) or an electronic device or system (e.g., a computer, smart phone, server, etc.).